Pedophilia, according to DSM-IV, involves “over a period of at least 6 months, recurrent intense sexually arousing fantasies, sexual urges, or behaviors involving sexual activity with a prepubescent child or children (generally age 13 years or younger).” The person must be at least 16 years old and more than 5 years older than the child. Although most pedophiles are males, there is a growing literature regarding sexual behavior between women and children.

The sexual attraction of the pedophile should be specified as to males, females, or both. Attraction to girls is more common than attraction to boys. However, pedophiles who are attracted to boys tend to have had more involvement with different children than those attracted to girls. Pedophiles attracted to both sexes usually prefer younger children. Pedophiles typically have highly specific age ranges and physical characteristics that define the children whom they find arousing. There is great variety in the types of sexualized activities they engage in with children. Some pedophilic relationships involve close emotional bonding.

Pedophilia is also coded as exclusive type, for individuals who are attracted only to children, or nonexclusive. Most male pedophiles who are attracted to boys are not interested in mature males and thus would not be considered homosexual. Nonexclusive pedophiles are usually heterosexual in terms of their adult sexual interests. Nonexclusive pedophilia may be also coded if limited to incest. Nonexclusive pedophilia also might be found in examples of regressed behavior, particularly if the sexual fantasies or behavior are manifested with reference to only one child and situation. Nonexclusive or regressed pedophilic behavior may be more likely to occur during times of stress. However, a diagnosis of pedophilia requires at least 6 months of recurrent sexually arousing fantasies, urges, or behaviors; isolated sexual activity with children is not sufficient evidence for diagnosis.

Some cases of pedophilia are associated with histories of having been sexually abused as a child. Pedophilia can also coexist with sexual sadism or lust murder, although this is rare. In most cases, pedophiles attempt to develop otherwise positive relationships with children.

Although adolescents may be defined as children according to the law, a primary and exclusive sexual attraction to adolescents in an adult would be ephebophilia, a paraphilia not otherwise specified.